Starting from the third item, the number of each item is the sum of the first two items.

(2)①=( 1+ 1+ 1)×2=6

②=( 1+ 1+ 1+2)×2= 10

③=( 1+2+ 1+ 1+。 3)×2= 16

④=( 1+ 1+3+ 1+2+5)=26

Law: ① twice as much as 3, ② twice as much as 5,

. . . . Attending is twice that of 13:

⑩=233×2=466.